(1) Field of the Invention
The present invention relates to an electronic parts automatic mounting apparatus used to mount tipped electronic parts, for example, such as resistors, capacitors or transistors (hereinafter referred to as tipped parts) on a print substrate, and more specifically to an electronic parts automatic mounting apparatus which recognizes the tipped electronic parts held by removing nozzles prior to mounting them on the print substrate so as to correct a deviation in position thereof.
(2) Prior Art
A conventional part recognizing apparatus in the electronic parts automatic mounting apparatus of this kind is disclosed in Japanese Patent Application Laid-Open No. 63-54000 previously filed by the present applicant, in which removing nozzles are vertically movably and detachably mounted on removing head portions which move in an X-Y direction, and in case where positions of the tipped electronic parts attracted and held by the removing nozzles are detected, a light from a light source is irradiated on a lead wire of the tipped electronic part through a diffusion plate through which the removing nozzle extends and the position is picked up by an image pickup unit.
However, in such a conventional apparatus as described above, normally, the removing nozzles have an exchangeability so as to correspond to a small-diameter nozzle for attracting a small-sized part and a large-diameter nozzle for attracting a relatively large-sized part. When the small-sized part is attracted by the small-diameter nozzle, the diameter of a nozzle mounting portion is excessively large, and a diffused light irradiated through the diffusion plate does not sufficiently reach the lead wire of the small-sized part due to the formation of a hole through which the nozzle extends or the like, failing to accomplish the image pickup with accuracy.
Furthermore, in Japanese Patent Application Laid-Open No. 63-298573 which discloses an arrangement wherein an illumination portion and a diffusion plate are provided on a single removing nozzle, in case where a large-sized tipped electronic part is recognized, it is necessary to make the illumination portion large according to the size and shape or the like of parts.
In addition, other means for recognizing tipped electronic parts attacted and held by the removing nozzles through illumination means are disclosed in Japanese Patent Publication No. 62-13152 (a specification filed corresponding to U.S. Pat. No. 4,747,198), in which a removing head portion on which a removing nozzle is mounted is seen through over a predetermined range externally of at least an outer peripheral surface of the removing nozzle whereby the peripheral portion of the removing nozzle can be seen through a transparent member within the head portion from a portion above the removing head portion.
However, in the recognizing means of this kind for the tipped electronic parts attracted and held by the removing nozzles, an area occupied by one removing nozzle for attracting and holding, for example, a large-sized tipped electronic part, becomes large, and if a plurality of removing nozzles are mounted in a single removing head unit, the apparatus inevitably becomes large-sized.